JP2008209391A - Routine operated seismic source utilizing electromagnetic coil - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a precise routine operated seismic source utilizing electromagnetic coil, which is quite a new type precise-controlled routine operated seismic source capable of generating large-scale artificial shaking by utilizing a superconducting coil or the like where a large current is caused to flow by making electric resistance zero to thereby generate a high magnetic field and using the electromagnetic force of repulsive force or attraction force of the high magnetic field, and which is compact, require extremely small consumption energy, and has a semipermanent lifetime as compared with the conventional precise-controlled routine operated seismic source. <P>SOLUTION: In this routine operated seismic source, a permanent magnet or a direct current superconducting electromagnetic coil and an alternating current superconducting electromagnetic coil are disposed adjacent to each other, and also one of the permanent magnet or the direct current superconducting electromagnetic coil and the alternating current superconducting electromagnetic coil is fixed in an optional position, thereby utilizing the shaking force generated due to the electromagnetic force of the permanent magnet or the direct current superconducting electromagnetic coil and the alternating current superconducting electromagnetic coil. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention mainly generates a stationary elastic wave artificially for monitoring and observing underground structures and conditions mainly for early detection of earthquakes, and is used to accurately transmit a steady controlled source (Accurately Controlled Routine). Operated Seismic Source, ACROSS).

  Conventionally, a precise controlled steady-state source using electromagnetic force generated by a superconducting coil has not been considered. At present, mechanically controlled devices using centrifugal force are used as precision controlled steady-state earthquake sources to obtain large steady-state vibrations. However, bearing loss is extremely large due to mechanical contact, and there are problems with noise and life. is there. Recently, it has been proposed to use a hydrostatic bearing as a support bearing, and a hypocenter that gives an eccentric load of about 200 kgf has been prototyped and has obtained good results. There are difficulties such as increased power consumption due to increased bearing flow rate and large energy loss due to windage because large and heavy objects rotate in the air. In addition, centrifugal force-based energy-saving stationary earthquake sources using pinned superconducting magnetic levitation have been proposed, but in any case, at extremely low frequencies of 1 Hz or less, the size of the device, the mass consumption of energy, and the cost There are many problems such as increase, and it is difficult to manufacture.

  FIG. 1 shows a structural diagram of a precision controlled stationary earthquake source using a mechanical bearing (roller bearing) conventionally used. The eccentric mass is created by providing a notch in a part of a large shaft as shown in FIG. For this reason, the bearing must support a large and heavy shaft and be able to withstand the centrifugal force generated by high-speed rotation in the radial direction, causing heat generation of the bearing, increasing drive power, and further destroying the bearing. Has a problem of reaching.

FIG. 2 shows a conceptual diagram of a precision controlled stationary earthquake source using a pinned superconducting magnetic levitation guide that magnetically levitates a rotating body in a non-contact manner. A magnetic rail composed of permanent magnets and magnetic material is placed on the inner surface of the cylinder, and a vehicle with a bulk superconductor installed is magnetically levitated on the inner surface side in a non-contact manner using the pinning effect that is one of the superconducting phenomena. This shows the precise controlled steady-state epicenter. In superconducting magnetic levitation, the mass of the rotating vehicle itself becomes an eccentric mass. For example, as shown in FIG. 3, a vehicle having a weight of 5 kg generates a large centrifugal force of several tens of tons by rotation. However, it is difficult to generate a large generated force at a rotational speed of several rps or less. Since the centrifugal force F is given by F = mRω ² (m: rotor mass, R: rotational radius, ω: angular velocity 2πf, f: rotational speed per second), especially at rotational speeds of 0.5 rps or less, ω ^{Since 2} is smaller than the gravitational acceleration, to obtain a generated force of 5 tons as shown in FIG. 4, at the rotational speed of 0.5 rps or less, the weight of the rotor that becomes an eccentric load becomes larger, and the generated force is no longer large due to centrifugal force. It becomes difficult to produce.
Japanese Patent Laid-Open No. 10-142345 JP 2006-250568 A

  An object of the present invention is to generate a high magnetic field by using a superconducting magnetic coil that can flow a large current with zero electrical resistance, and to generate a large-scale artificial vibration by a high magnetic field repulsive force or an attractive electromagnetic force. It is a new type of precision controlled steady-state epicenter, which is to provide a precision controlled steady-state source that is smaller and has an anti-permanent lifetime that is much smaller in drive and energy consumption than conventional precision controlled steady-state sources.

The above problems are solved by the following means.
(1) A stationary earthquake source in which a permanent magnet or a DC electromagnetic coil and an AC electromagnetic coil are arranged adjacent to each other and electromagnetic force between the permanent magnet or the DC electromagnetic coil and the AC electromagnetic coil is used.
(2) A permanent magnet or a DC electromagnetic coil and an AC electromagnetic coil are arranged adjacent to each other, and either the permanent magnet or the DC electromagnetic coil and the AC electromagnetic coil are fixed at an arbitrary position, thereby allowing the permanent magnet or the DC electromagnetic coil to be fixed. Stationary seismic source using excitation force generated due to electromagnetic force between coil and AC electromagnetic coil.
(3) The stationary seismic source according to (2), wherein the permanent magnet or the DC electromagnetic coil is directly connected to both side surfaces of the AC electromagnetic coil, and the AC electromagnetic coil is fixed at an arbitrary position.
(4) A permanent magnet or a DC electromagnetic coil integrated with a coupler that connects the ground and the coil is arranged on both sides of the AC electromagnetic coil, and the AC electromagnetic coil is fixed at an arbitrary position. The stationary seismic source described in (2).
(5) a first coupler for connecting the ground and the coil, a first permanent magnet or a DC electromagnetic coil disposed on one side of the AC electromagnetic coil, and a second coupler for connecting the ground and the coil; A stationary earthquake source in which a second permanent magnet or a DC electromagnetic coil is disposed on the other side surface of the AC electromagnetic coil, the AC electromagnetic coil being fixed at an arbitrary position, and a first coupler and a second permanent magnet or DC The stationary seismic source according to (2), wherein the electromagnetic coil and the second coupler and the first permanent magnet or the direct current electromagnetic coil are connected in pairs.
(6) The stationary earthquake source according to any one of (1) to (5), wherein at least one of the DC electromagnetic coil and the AC electromagnetic coil is a superconducting magnetic coil.

  According to the present invention, by using an electromagnetic force generated by a superconducting magnetic coil or the like, a large output vibration generating force is reduced in size, has little loss, has a semi-permanent life, and is generated in proportion to an arbitrary current waveform. Therefore, it is possible to realize a precise control stationary earthquake source that is easy to control and can operate from a very low frequency region to a high frequency region.

  Furthermore, according to the configuration of claims 3 and 4, a direct current is passed through the two direct current superconducting magnetic coils to generate a direct current magnetic field, and an alternating current is passed through the alternating current superconducting magnetic coil installed between the two direct current superconducting magnetic coils. Between the superconducting coil and the AC superconducting magnetic coil, a repulsive force and an attractive electromagnetic force proportional to the AC current are generated. Since this electromagnetic force F is proportional to the current I flowing in the magnetic field B (F∝BI), it is generated in proportion to the frequency, current waveform, current value, etc. of the alternating current, that is, a direct current electromagnetic coil or an alternating current. An excitation force is generated by fixing one of the electromagnetic coils at an arbitrary position, and a precise controlled steady-state earthquake source is created.

The present invention is characterized in that an electromagnetic force is used instead of a centrifugal force using a superconducting magnetic coil or the like in order to create a small and large generating force from a very low vibration frequency region, and an example of a basic structure is As shown in FIG. 5, it consists of two DC superconducting magnetic coils and an AC superconducting magnetic coil installed between them. Since the superconducting magnetic coil is cooled and kept below the liquid nitrogen temperature, its periphery is surrounded by a vacuum heat insulating layer. The two DC superconducting magnetic coils are directly connected, and after excitation, the superconducting switch can be short-circuited to form a permanent magnet in the permanent current mode. Moreover, it is also possible to form a pinned permanent magnet using a bulk superconductor instead of the superconducting magnetic coil.
The two DC superconducting magnet coils are excited to polarities facing each other, and by flowing an AC current through the intermediate AC superconducting magnet coil, they are attracted to one DC superconducting magnet coil and repel each other DC superconducting magnet coil As a result, an electromagnetic force corresponding to the AC waveform, frequency, and current value is generated.

  As an example, the diameter of the superconducting magnetic coil is 300 mm, the inner diameter is 150 mm, the width of the two DC superconducting coils is 30 mm (the number of turns: 480 times of superconducting wire), the width of the AC superconducting magnetic coil is 50 mm (the number of turns: 800 times of superconducting wire), In the configuration of 30 mm between the coils, a very small precision steady-state source having a vibration generating force of 5 tons can be obtained by flowing a current of 200 A.

  FIG. 6 shows the entire configuration including the power source, refrigerator, etc. of the precision controlled steady-state epicenter shown in FIG. When a permanent magnet is used in place of the DC superconducting magnetic coil, cooling is not necessary and the structure of the portion is simplified. However, at present, the open surface magnetic field of the obtained rare earth permanent magnet is about 0.5 T, and therefore, to obtain a generated force of 5 tons, the system becomes a rather large system due to the square relationship of the magnetic flux density B.

Next, FIGS. 7 to 8 show conceptual diagrams of a precisely controlled stationary earthquake source using a superconducting magnetic coil.
7 shows a DC electromagnet integrated with a coupler that connects the ground and the coil on both sides of an AC superconducting magnetic coil, and a variable current is passed through the center AC electromagnet to cause the coupler to react with the electromagnets on both sides. It is a repulsive stationary source that gives ground motion through the ground. The current flowing through the superconducting magnetic coil in the center is a bias current as shown in FIG. 9, and a compressive force is always applied to the coupler 1 and the coupler 2.
In FIG. 7, a superconducting magnetic coil or a permanent magnet using a permanent magnet or a bulk superconductor may be used instead of the DC electromagnet. A bias magnetic field can also be applied by passing a direct current using another superconducting magnetic coil.

FIG. 8 shows a suction-type stationary seismic source that vibrates in the ground by acting on the DC electromagnets on both sides and the superconducting magnetic coil in the center with constant attraction. The direct current electromagnet 1 and the coupler 2 and the direct current electromagnet 2 and the coupler 1 are connected in pairs, and a variable compression force is always applied to the coupler as in the repulsion type.
In this structure, since the same repulsive force or attractive force is applied to the central AC superconducting magnetic coil from both sides, the central superconducting magnetic coil is firmly fixed in the ground.
For this reason, a stationary seismic source having a large excitation force even in a low frequency region of about 0 to several Hz becomes possible.

Note that the above example is merely for facilitating understanding of the present invention, and the present invention is not limited to this. That is, modifications and other aspects based on the technical idea of the present invention are naturally included in the present invention.
For example, a stationary earthquake source having two DC superconducting magnet coils and an AC superconducting magnet coil installed between them is illustrated. However, a single DC superconducting magnet coil and an AC superconducting magnet coil may be used. In addition, one or both of the AC electromagnetic coils may be normal (normal conducting) electromagnetic coils.

Structure of 20t-class precision controlled steady-state epicenter with mechanical bearing support in operation Conceptual diagram of a cylindrical precision controlled steady-state source with a proposed superconducting magnetic levitation support Calculated value of centrifugal force with respect to rotational speed at 5 kg of rotating vehicle load Relationship between rotating body weight and rotating radius with frequency of 3Hz or less necessary for obtaining centrifugal force of 5t as parameter Schematic diagram of a linear precision controlled steady-state source using the superconducting magnetic coil of the present invention Configuration diagram of cooling, vacuum insulation, etc. for the superconductor of the linear precision controlled steady-state epicenter of the present invention Conceptual diagram of repulsive precision controlled stationary seismic source using superconducting magnetic coil Conceptual diagram of a suction-type precision controlled stationary source using superconducting magnetic coils Bias current diagram

Claims (6)

  A stationary earthquake source in which a permanent magnet or a direct current electromagnetic coil and an alternating current electromagnetic coil are disposed adjacent to each other and electromagnetic force between the permanent magnet or the direct current electromagnetic coil and the alternating current electromagnetic coil is used.   A permanent magnet or a DC electromagnetic coil and an AC electromagnetic coil are arranged adjacent to each other, and either the permanent magnet or the DC electromagnetic coil or the AC electromagnetic coil is fixed at an arbitrary position, whereby the permanent magnet or the DC electromagnetic coil and the AC are exchanged. Stationary seismic source using excitation force generated due to electromagnetic force between electromagnetic coils.   The stationary earthquake source according to claim 2, wherein the permanent magnet or the direct current electromagnetic coil is directly connected to both side surfaces of the alternating current electromagnetic coil, and the alternating current electromagnetic coil is fixed at an arbitrary position.   A permanent magnet or a DC electromagnetic coil integrated with a coupler for connecting the ground and the coil is disposed on both sides of the AC electromagnetic coil, and the AC electromagnetic coil is fixed at an arbitrary position. The steady-state epicenter of Item 2.   The first coupler and the first permanent magnet or DC electromagnetic coil for connecting the ground and the coil are arranged on one side surface of the AC electromagnetic coil, and the second coupler and the second for connecting the ground and the coil. A stationary earthquake source in which a permanent magnet or a DC electromagnetic coil is disposed on the other side surface of the AC electromagnetic coil, the AC electromagnetic coil being fixed at an arbitrary position, and a first coupler and a second permanent magnet or a DC electromagnetic coil, The stationary earthquake source according to claim 2, wherein the second coupler and the first permanent magnet or DC electromagnetic coil are connected in pairs.   The stationary earthquake source according to any one of claims 1 to 5, wherein at least one of the DC electromagnetic coil and the AC electromagnetic coil is a superconducting magnetic coil.